


kiss me beloved, say you’re my own

by kiriya



Category: Kamen Rider Build
Genre: Anal Fingering, Anal Sex, Battle Scars, Boys Kissing, First Time, Love Confessions, M/M, Porn with Feelings, Praise Kink, Rimming, sex banter
Language: English
Status: Completed
Published: 2018-10-28
Updated: 2018-10-28
Packaged: 2019-08-09 03:31:30
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,001
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16442177
Author URL: https://archiveofourown.org/users/kiriya/pseuds/kiriya
Summary: Banjou Ryuga is in love with Kiryuu Sento, and wants to give him everything he has.





	kiss me beloved, say you’re my own

My love and devotion are yours, yours alone

**Kiss me beloved, say you're my own**

.

They stumble through the door fused at the lips. The force is brutal, hard enough to bruise but Ryuga is used to it. Their kisses were always like this, desperate, all lips and tongue and teeth, caught in-between battles they may not live to see the end of. They weren’t good - Sento didn’t have the experience to make them so  - but Ryuga did not care. The feeling of seeing the sun glittering off Build’s new form lingers in his veins, and his blood buzzes with the adrenaline of victory. Ryuga tastes the metallic tang of blood on the tip of his tongue (Sento must have split Ryuga’s lip _again)_ , but doesn’t pull away. All Ryuga feels, thinks, wants is Sento.

Sento has an arm thrown around Ryuga’s neck, and another in his hair, pulling his braids loose and holding him as close as possible. The entire lines of their bodies is pressed together, not leaving an inch of space of between them. Warmth crawls over his skin everywhere Sento touches, and Ryuga feels as if he could melt into him until they’re one.

Ryuga moves his hands up the planes of Sento’s body, feeling and touching. He kicks the door behind them shut. The slam shakes the frame. It doesn’t matter though, no one’s home. Kazumi insisted to everyone he and Sento needed the time alone, after all the time they spent part. He hears the wood crack, but not splinter.

It’s been so long since Ryuga has felt this. It’s been so long since he’s basked in everything good and bright that is Kiryuu Sento, and even longer since he felt his skin under his lips. Sento was barely lucid, unable to think past the pain of the poison, when Ryuga kissed him last. It was on the forehead: a tender goodbye.

From that, from being possessed, to fucking Katsuragi Takumi, Ryuga cried enough for a lifetime, thinking he’d never get _this_ again.

Ryuga moans as they refind their rhythm.  He curls his fingers in back of the other man’s button down, and it tears in his hands.

Ryuga forgets how strong he’s become.

“You look awful in this this.”  He says when he tears away from the kiss. Hot, heavy breaths fill the small space between them, and Ryuga scowls at the unflattering pale color. He feels the fragile fabric of the button-down between his thumb and his forefinger, and looks back up at Sento, searching for permission.

“It’s Kasturugi’s.“

It’s all the consent he needs to tear it down the center.

“Don’t say his name,” He orders, as the plastic buttons scarp the floor. Ryuga dives for the newly exposed skin of his neck. He starts with hot, wet kisses, and Sento, sucking in his breath, brings an encouraging hand into the back of his head.

Ryuga bites down.

”Say mine,” he insists.

Then, he kisses Sento, softly. He’s never acted so bold before. Usually, they don’t speak between kisses - that’s not true, they bicker, _a lot_ \- but they’ve never had sex and Ryuga has never asked. He’d wanted it to be more than the desperate moments they’d given in to how they felt about each other, despite all the talk of _waiting_ to be together. Ryuga wanted to take his time and make Sento feel good, but now, almost having lost him forever, waiting seems so stupid.

The instant their lips slide together, Sento’s pressing into him as hard as before. Sento moans into his mouth, and Ryuga licks up the sound, savoring the way the moan vibrates against his sensitive lips, bruised and tingling from the intensity of their kisses.

Ryuga holds onto Sento like he might drown if he lets go. He needs this. He needs to get rid of the coldness he gained in Sento’s absence; he needs to drink in those eyes and recognize the man he loves there.

Ryuga grunts into the kiss, and grabs Sento’s hips, urging him back. They step towards the bed, fused at the lips, and the denim of Sento’s jeans gives easily under Ryuga’s strong hands. The torn strips of denim fall around his mismatched shoes, and once the back of Sento’s knees hit the bed, Ryuga holds him in a one last kiss, long, loving and deep, before pushing him back.

The force of it makes the old mattress creak, and the sight of Sento winded from the sudden movement — wide eyes, messy, hair and swollen lips — is intoxicating.

Ryuga hopes he looks half as enticing as Sento does, locking eyes with him as they crawl up the bed.

“I’m your first, right?” Ryuga asks, holding himself up by his elbows, looking into Sento’s dark, needy eyes.

Ryuga knows the answer to his question, of course, but he just wants to hear him, the arrogant, genius hero of justice he’s come to hold so close to his heart. He expects Sento to feign surprise and tease him, or cover with a narcissistic comment. Like, there must have been plenty of men because he’s such a handsome genius.

The thought makes him feel oddly soft, because it’s so _Sento_. He brings his hand to the side of Sento’s face and his thumb brushes against the rough edge of a bandage, juxtaposing the softness of his skin.

“You’re my only,” Sento murmurs, defying his expectations.

The tender reply makes Ryuga feel like flowers are blossoming in his chest. The sudden feeling of softness is alarming at first, but he wants nothing more to melt into this soft feeling and drown in everything Sento.

They’ve never said the three words before: _I love you_. They’re supposed to be waiting, after all. _The hero gets the love interest in the end_ , Sento says, but Ryuga suspects it’s the guilt that makes him say so. Still, Ryuga feels the awareness deep in his soul: he’s in love with Kiryuu Sento.

They won today. Twice this month, he lost Sento. When it was Katsuragi, he thought was forever, and today, Ryuga got him _back_. They share a bond so intense the universe would bend accommodate to it; Ryuga’s entire being vibrates with the euphoria of love and victory.

Ryuga leans down to kiss him, a soft pressing of lips, gentle in a way they’ve seldom been able to share amongst such despairing times.

“You’re my best match,” he whispers.

Sento scoffs and smiles, expressing the fond exasperation Ryuga’s come to associate Kiryuu Sento with so well. It only exacerbates the fluttering in his chest.

Sento keens into him and kisses him. Ryuga savors it with a moan; he doesn’t ever think he’ll get used to how good the shape of his mouth feels between his lips, and how reactive he is to his touch. The power, how he feels, it’s all so potent. Ryuga grabs Sento’s bottom lip between his teeth, and Sento twists his fist in the cotton of his shirt so hard it comes apart.  

Ryuga withdraws from the kiss, and pulls the torn fabric over the of his head. He has plenty other shirts, and smiles back down at Sento, whose hands are making their way up his bare skin. Ryuga covers of Sento’s wandering hands with his own.

“I’ll be gentle, okay?” Ryuga assures him.

He wants to settle any of Sento’s lingering nerves, if there are any, before they start. He’s Sento’s first, he wants to be Sento’s _only_. They’ve become so wrapped up in each other — so inextricable, like tangled ivy  — Ryuga can’t imagine a life without Kiryuu Sento.

Sento blinks at his exposed abdomen a few times, dazzled, before replying. It’s good ego boost, and makes something hot curl in his gut.

“Please,” Sento says — mockery, not begging — because of course, if he’s nervous, he won’t show it. “I’m a virgin, but I’m not fragile.”

“Mmm,” Ryuga hums, letting the comment go. There are other ways to rile him, and the bruises and scarred-over wounds on both their skin lend themselves well to his assertion of durability. Ryuga still thinks Sento’s overestimating himself, though. Sento’s hands come up to touch his pecs, and Ryuga’s lips curve into a smirk. Deliberately, he tenses: a playful flex that reveals the sculpted lines of his biceps and abdomen. “You like my muscles, huh?”

“Maybe,” Sento replies, idly stroking a finger over his bicep. He tilts his head up at him, and his eyes are sharp but dark with lust, “Maybe I like you for your intelligence.”

“Uh-huh, sure.” It’s so Sento, Ryuga feels a little ache, like someone has snapped just the right puzzle piece into the jigsaw-shaped gap in his chest. “I just like you ‘cause you’re pretty.”

With that, Ryuga leans into capture him in another kiss, and he feels Sento’s hands move between them: to the front of Ryuga’s jeans.

“Eager?” Ryuga asks wryly.

Sento rolls his eyes, “You‘re drawing this out.”

“Can you blame me?,” He strokes the edge of his finger along Sento’s sharp hips, “You’re rarely so agreeable.”

“Big word, musclehead.”

“Why do you always gotta underestimate me? I’m smarter than you think.”

“Nonsense. I think the world of you.”

“You do? Tell me more. About how I’m your strong handsome hero who you can’t live without.”

“Don’t push it,” He narrows his eyes and dips his fingers deeper into Banjou’s waistband. “And stop talking so much.”

“Can’t help it,” Ryuga mumbles after another sweet kiss, “Missed you.”

He kisses him some more, savoring the feel of Sento’s soft lips sliding against his, and lets Sento undo his jeans. He does the same, pushing down Sento’s underwear to his knees so he can kick them off, along with his socks and shoes, and Sento does the same for him.

They’d done things before, hand and mouth stuff when they were desperate for each other and didn’t have a risk of being caught, but Ryuga’s never seen him him fully naked.

He’s so in love, he’s temporarily stunned by his beauty. Sento doesn’t have a body quite as sculpted as Ryuga’s. His shoulders are still narrow, despite all the battle, but every inch of him is lean and his cock is hard between them. Sento has long legs that are incredibly seductive, and all of his exposed skin, still bruised in some places, looks so inviting.

He wets his lips unconsciously, and splays his fingers across Sento’s warm stomach. The skin there is soft in a way Ryuga’s not used to feeling on his own body, but when he moves his fingers, he feels the familiar rise of scars, fresh and pink against his pale skin.

“You’re so beautiful,” Ryuga tells him, a little breath-taken.

“You’re a sap,” Sento says, a mock-irritated tease.

So what? He’s sweet on Sento and doesn’t care to hide it.

“Hell yeah I am,”  he replies, proud. Then, he lowers his voice, softening its edges. “Are you ready?”

“Yes,” Sento assures him. “Best match, Build up, all that.”

“God,” Ryuga sighs, reaching over Sento to grab one of the pillows next to his head. “I missed you like hell.”

“Of course you did,” Sento replies, “What’s a sidekick without his hero?”

“Mmm ...  You looked good with white hair, though,” Ryuga informs him while dragging his hand along the curve of Sento’s ass. Sento obligingly raises his hips. Sento’s cock is hard, red, and leaking against his stomach. It’s an emboldening sight,  “Almost as good as you look waiting for me to fuck you.”

“Shut up, musclehead,” he grumbles at him, but Ryuga notices the color of his cheeks deepen.

“Alright,” Ryuga concedes. He wraps his hands under Sento’s thighs, lifting his legs so that they’re wrapped high around Ryuga’s waist. It’s a good view. “I can’t wait either, you look so fucking good.”

Ryuga splays his hand across Sento’s chest, feeling the strength of his heartbeat there. There’s something in Sento’s eyes when Ryuga says _he looks good_ , something in the way his body becomes more pliable … Ryuga thinks he’s already found something Sento likes.  

With his free hand, Ryuga reaches for the nightstand. He grabs the lube. Ryuga flicks open the cap, and presses it to the tips of two fingers.

“Banjou,” Sento hisses when he pushes into him with one finger.

Ryuga laughs. Of course, even now, Sento refuses to call him anything other than musclehead or his family name, but the way Sento’s back arches when Ryuga enters him is so sweet, he lets it go.

Ryuga leans forward, using the weight of palm to push him back down into the sheets. Ryuga holds him there as his muscles clench around him, and kisses his face, the side of his jaw, and the hollow of his ear.

“Relax,” he whispers against his skin. It’s good to be close again, “I got you.”

He feels Sento chest expand against his palm, and ease around his fingers. Ryuga pushes in further, slowly, and adores Sento’s neck with his mouth, kissing, licking, sucking. Ryuga gets satisfied little cries with the occasional bite.

Ryuga moves down his chest, his stomach. He savors every inch of warm skin, kisses every bruise and scar. He doesn’t react when Ryuga presses the flat of his tongue against his nipple, but his whole body jerks when his breath ghosts the sharp edges of his hips. Eventually, he adds another slick fingers.

He writhes as much as he can under the solid weight of his palm and kicks out mindlessly (it’s endearing and fittingly rabbit-like). Ryuga stretches him out and teases his hips with the tip of his tongue and barely there kisses. Once, he bites, and Sento yells his name. He wraps a hand in Ryuga’s hair instead of in the sheets, filling Ryuga with a hot thrum of satisfaction that makes his cock throb.

He’s going slow… Agonizingly so. It’s Sento’s first time. Ryuga doesn’t want to hurt him, the thought makes him sick, but he definitely wants to be a tease.

He loves Sento with everything he’s got, but Sento _is_ a jerk and nothing would give Ryuga greater satisfaction than to see him completely undone. Maybe Ryuga wants to punish him a little too, for being so stupid and recklessly self-sacrificial for Ryuga’s sake. As if Ryuga could ever be okay in a world without him.

“That’s good, Sento,” he murmurs, so close he can feel the heat of own breath against Sento’s skin, “You’re doing so good.”

Ryuga knows he was right Sento likes to praised, because he immediately feels Sento’s fingers tighten in his hair.

“Banjou,” he whines, grinding down onto his fingers so that Ryuga’s knuckle-deep.

“You like getting your ego stroked though, huh?,” He twists his finger inside Sento, as if to prove his point. “Figures. You want more?”

“ _Yes_ ,” Sento hisses. He narrows his eyes, “This is the worst. You’re being a tease.”

“Yeah,” Ryuga concedes, picking up the pace of his thrusts. He runs his free hand up the inside of Sento’s thigh, nudging them further apart. He doesn’t want to draw this out so much that Sento suffers, “Not gonna fuck you just yet, but if you want more, I’ll give it to you.”

Sento takes a deep breath and sighs, “ _Please_.”

Ryuga smiles at that — When has Sento ever been so polite? — and moves his lips away from Sento’s hips. He moves lower. Ryuga pulls free and holds his cheeks open with both hands, letting his tongue replace his fingers. Sento whines at the loss, at first, a high-pitching keening sound that sends a hot bolt of desire through him, but the sounds Sento makes afterward with every well-placed stroke and flick make it a worthwhile wait.

Every sound he makes is sinful, and Sento holds his hair like his life depends on it, pulling his braids apart and creating a small, blissful sear of pain.

Ryuga lets his fingers join his tongue again, one, two, as many as three before he moves up to absorb the sight of the genius physicist unravelled. He wants to commit every detail of him to memory: the pleased knit of brow, his teeth being dragged over his lip, the color staining his cheeks. _His_ Sento coming undone for him. He never wants to lose this; he never wants to look into those beautiful, dark eyes and feel anything but this. The more he thinks about it, the more his heart aches.

He feels the words bubbling up his throat, but he doesn’t say them. He doesn’t think Sento would want to hear it now, while he’s more concerned greedily fucking himself on Ryuga’s fingers. He will say it though, before this all comes to an end.

_I love you._

Ryuga grabs a condom from the nightstand and rips the packet open with his teeth. His cock aches between his legs and Ryuga feels hot all over, thinking about good Sento’s gonna feel.  

Ryuga pulls his fingers free, making Sento whimper again, and shifts up the bed, aligning his hips with Sento’s ass. He rolls the latex down the length and slicks his cock up with a handful of lube.

“Gonna fuck you. Gonna make you feel good, yeah?” He means to sound good, collected and in control of himself, but the promise of satisfaction is making him dizzy and he sounds hoarse and heady. He loves Sento, he loves that he has Sento back and that he can touch him and lose himself in him like this. “Gonna make you feel so good, Sento.”

Sento’s fingers brush his biceps, pleading, “Banjou, please.”

With one hand on Sento’s shoulder and the other around the base of his cock, Ryuga pushes slowly inside Sento. He groans, getting sucked in inch-by-inch by the blissful heat. He’s hot, wet, everything Ryuga imagined he would be. Better even, even if it’s just for the way Sento reacts. He throws his head back and moans as he pushes in, tangling his fingers in the sheets as he stretches to accommodate Ryuga. All he wants to make Sento feel good, and the sight does things to him, makes Ryuga want to fuck him with abandon and cover his exposed throat with bites and kisses.

But he can’t yet.

“How does that feel?” He asks, trying to keep his voice steady. The feeling is a bit overwhelming. It’s been awhile, since before prison, but he doesn’t let himself think about that too much, lest he ruin this moment for himself.

“Banjou,” he says, breathy and needy, as little in control as he is. Sento swallows hard and nods, regaining a bit of composure. He squirms a bit, “Good. It feels good.”

“ _Good_ ,” Ryuga insists. He wets his lips, looking down at Sento. He looks so good, flushed and eager. “You feel so fucking good, Sento. I’m gonna make you feel so good, you’ll never be able to forget.”

Sento wiggles his hips, impatient, “I won’t.”

Ryuga peers up at Sento through brown, sweat damp bangs and gives Sento a crooked smile, “Damn right.”

Then, Ryuga starts moving, shallow thrusts that make Sento moan softly. Hands on his hip, he watches his cock disappear into Sento, The way Sento’s muscle flutter around his cock is hot and sweet, and when he’s ready, he establishes a pace, slow and deep, making Sento release little contented sighs of his name.

“Banjou. Banjou.”

He watches his red, swollen lips part around his name. Everything Sento does is memorizing because it’s him: the man he loves, the object of his devotion. Him squeezing and loosening around him is so fucking good, Ryuga hasn’t felt anything like it in a long time.

“You’re so good, Sento,” he tells him, meeting his dark, shiny eyes,  “I can’t get enough of you. Could never, no matter much I tried.”

Sento moans and curls his fingers in the sheets. Ryuga braces his hand on either side of Sento’s head, and leans down, savoring their closeness and the heat radiating off Sento’s skin. He presses their scarred stomaches together, so Sento can grind up against him. The movement changes the angle of his thrusts slightly, raising the pitch of Sento’s moans. His thrusts are long and deliberate, an easy pace that’s easy for Sento to match, bucking down on him. With a deep, well-placed thrust, Sento seethes and takes his hands out of the sheets to wraps around Ryuga’s shoulders.

“More,” Sento says, while digging his nails into the soft skin that gives above hard muscle. He squeezes his thighs around Ryuga’s waist, “I can take it.”

Ryuga doesn’t question him. He loves Sento and wants to give him everything he has. He pulls out, almost completely, and then sinks back in one quick motion. Sento bites down on his bottom lip, stifling a high-pitched whimper. Ryuga quickens his pace, watching Sento become drunk on his cock, but keeps thrusts deliberate, getting into Sento as deep as possible, hitting just the right spot that makes his lips part and his eyes sparkle.

Watching him is intoxicating: barely closed eyes, pink cheeks, and messy hair. It tugs something loose within him, something wild and powerful and loving all at the same time.

He gives into it, getting faster and more reckless with his pace. Sento bites his lip, holding back his needy little moans and raking his nails down Ryuga’s back.

“Fuck, Sento,” Ryuga says, caught up in it. “Make noise for me. I need you, Sento, you hear me. Don’t leave me.”

“Never,” The word is caught up in a breathless, heady sigh. Sento’s arching his back, pressing the flush of his chest against his. His fingers curl against his shoulders, “Not without a fight.”

 

Ryuga groans, and takes Sento’s wrists from his shoulders. Ryuga pins them to each side of his head and thrusts into him hard. He keeps up that pace, fast and merciless. Sento obliges him, openly moaning his name — the pitch gets higher with each thrust — and Ryuga lets himself be consumed by everything Sento (the sight, sound, and feel of him), until he hears wood splinter beneath them.

He slows down then and releases one of Sento’s hands. He presses his palm to Sento’s and laces their fingers together. Ryuga, approaching his edge, spits into his other hand — Who knows where the lube is now? — and starts stroking Sento’s cock between them while fucking him slow.

“M’close,” Ryuga mumbles.

Sento peers up at him through his dark lashes.

“Banjou,” Sento sighs, and Ryuga meets his eyes, dark and glazed over in pleasure, “I love you.”

Ryuga’s heart nearly splits from the pressure and his orgasm is crashes into him like a wave. He fucks Sento through it, rough, while lava moves through his veins and his whole body quivers. His thumb brushes over the head of Sento’s cock, and Sento screws his eyes shut and whines his name as he comes between their stomachs.

Ryuga props himself up by his elbows, and leans down to kiss him deeply, pressing the lines of their bodies together despite the mess. His whole body is warm and his head buzzes. The weight of keeping feelings to himself is gone, and all he can think is Sento, Sento, Sento.

“God. Sento,” Ryuga says between kisses he rains down on his face (his lips, the side of his the mouth, his cheek). The words are so heavy he wants to sob with the weight of them. “I love you so goddamn much.”

“Handsome, smart, heroic,” Sento lists off, idly tracing small circles on Ryuga’s bare back. He smirks at Ryuga, “It’s hard not to fall in love with the main character...”

Ryuga can’t help the laugh. Sento really wastes no time. He shakes his head and grins. “You’re something else, you know that?”

“Yes,” Sento agrees. He tilts his head towards Ryuga’s, eyes on his lips. “But I’m yours.”

Ryuga kisses him, loving and deep.

“Hell yeah you are.”

.

.

.

**My love and devotion are yours till I die.**

**Author's Note:**

> every comment and kudos add one more year to my life. 
> 
> i'm on twitter at @kaijinrights to discuss build, sento, and how in love these two are. thanks for @knickersaurus on twitter and @lorandias on ao3 for beta'ing this for me.


End file.
